Availability of PLA/SIS blends for packaging and medical applications.Part II: Contribution of stabilizer agents. (November 2022)

• Record Type: Journal Article
• Authors: Lupu (Luchian), Ana-Maria; Zaharescu, Traian; Râpă, Maria; Mariș, Marius; Iovu, Horia
• Is Part Of: Radiation physics and chemistry. Volume 201(2022)
• Publication Date: 2022-11
• Subjects: Radiation chemistry -- Periodicals; Radiometry -- Periodicals; Radiation -- Periodicals; Chimie sous rayonnement -- Périodiques; 539.2
• DOI: 10.1016/j.radphyschem.2022.110446
• Languages: English
• ISSNs: 0969-806X

Abstract

Abstract: The extending material durability of poly(lactic acid) (PLA)/styrene-isoprene-styrene copolymer (SIS) blend with 30% of SIS by the presence of acrylic acid (AA) and two stabilizers, caffeic acid or vanillic acid, is evaluated by γ-irradiation at technological doses (25 or 50 kGy) applied for sterilization or for the manufacturing of several commodities, medical, and packaging items, respectively, where an advanced exposure would affect the post-irradiation oxidation stability. The chemiluminescence investigations provide the onset oxidation temperature values from which the activation energies of degradation were calculated. Differential scanning calorimetry and infrared spectroscopy complete the evaluation of improvement efficiencies that characterize the thermal behavior of these materials. The effects of γ-exposure on the material properties are discussed relative to the radiolysis modifications occurred during radiation processing. The relevance of oxidation protectors is analyzed based on the efficient delay of ageing. The results are the qualification information for the packaging and medical products subjected to the radiation processing and radiation sterilization. Highlights: - The degradation of PLA/SIS starts priory in hydrocarbon component - The compound containing the lowest SIS concentration is the most stable - The irradiation causes a light crosslinking of hydrocarbon component - The thermal degradation of all compositions starts just before 100 o C